The key word of this paper is "transition", in a frame of evolution dynamics. The choice of model has its focus on innovation on return, on the distorsion between construction and perception, on the need of renoval for stimula and models thorn by long use.In section 1 we deal with phaenomena that are born and die without important oscillations. In section 2 we analyse some simple theoretical assumptions that lead to oscillatory systems, while in section 3 we present some applications to landscape and territorial analysis. Section 4 deals with semiotic phaenomena connected to the enjoyment of landscape-cultural mosaic, also keeping in mind the theoretical examples of section 2
